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Construction Safety

Safe Work Execution + Nudge Theory

Peter Furst | May 17, 2019

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Teenagers looking up

Statistics show that the construction industry tends to have a larger proportion of accidents in relation to the number of workers involved than many other industries. Accidents tend to disrupt the orderly production process and are costly. The "Domino Theory" proposed by W.H. Heinrich in the 1920s and modified by Frank Byrd in the 1970s indicates a series of events in a chain reaction, where one event affects the next one until ending in an adverse outcome such as an accident, injury, or loss.

The Domino Theory (see Figure 1) indicated that the last action leading to the resulting accident is invariable always taken by the worker. So, when conducting an accident investigation, the most likely step is to try to identify what the worker did that led to that outcome. This may be the reason why traditional safety management tends to focus on the worker for solutions to the improvement of project safety results.

Figure 2: Figure 1—Domino Effect or Chain Reaction

Traditional Work Site Safety Management

The traditional way safety management is addressed on a construction work site is for the safety practitioner to do an inspection of the work site as well as observe the crew engaged in performing their tasks. This is supposed to lead to identifying hazardous conditions as well as stopping and talking to any worker engaged in at-risk behavior. The safety practitioner utilizes an inspection worksheet, which is modeled after the Occupational Safety and Health Administration (OSHA) safety regulations. As discussed in our previous article, "Ensuring a Safe Construction Work Site" (October 2018), such safety inspections are an ineffective methodology to identify and change the unsafe behaviors of the workforce. Nor is it a highly effective way to manage and improve the work site's safety outcomes.

Since the focus of this inspection is to identify problems, or deficient worker behavior, the safety practitioner is functioning as the "safety cop"—identifying problems such as hazardous conditions and/or "writing workers up." In this scenario, the workforce perceives the safety practitioner in a negative light. The natural response to this might very well be resistance to; or ignoring whatever the safety practitioner may suggest as a solution to the situation. This tends to have a counterproductive outcome and does not benefit either the worker or the organization.

Construction work is "driven" by the schedule, so the focus tends to be on production. If the workforce's perception is that production is important to the project supervision, then anything that they deem will interfere with that is detrimental to their perceived job security. It is also possible that the "safe way" suggested by the safety practitioner might be perceived by the worker as taking more time or possibly be more difficult to perform. As a result, the suggested "safe way" may not be supported in the prevailing work situation.

Other means of trying to change the work practices in the field is to provide workers with some form of training, which primarily involves regurgitating the OSHA standards. The safety standards are primarily focused on conditions; therefore, they tend to be useful in ensuring that hazards involving physical conditions are addressed, but they are far from effective or even useful in changing behavior. The standards are not particularly useful in understanding the underlying causation or undesirable action or events.

Organizations may try to manage their workforce's safety performance by affecting a change in their work practices and/or behavior using OSHA safety standards information. But, unfortunately, this approach does little to effectively garner the expected results. Behavior can be impacted (changed) through operant conditioning. That involves providing sufficient feedback to change the behavior. The worker may precipitate the adverse event (accident) by virtue of different factors. These may include a lack of understanding, deficient information, or improper communication. The worker may make an error that may be skill-based, rule-based, or knowledge-based; it may possibly involve an error or omission, commission, timing, or sequencing. It may result from human dynamics involving the crew or the leader-member exchange (driven by the supervisor).

The supervisor may inadvertently be the cause of the undesirable outcome through poor planning, improper risk assessment, inappropriate task assignment, providing improper tools, setting production goals that are difficult to achieve, setting conflicting goals or objectives, creating a stressful work climate, playing favorites, not giving credit when credit is due, or a lack of fair treatment, to name a few. The operational as well as the organizational systems may create deficiencies in processes, procedures, or practices, which would create situations that are error provocative or may degrade the integrity of defenses created to act as a deterrent to workers making mistakes. The systems may also influence workers' perceptions, which will ultimately influence their behavior.

Since the worker-driven discrepancies are easier to identify than those driven by the systems, the organizations may decide to try to change the worker's behavior. They may devise the following.

  • Exclusion designs—these are work processes that make it impossible to make an error as workers engage in the work.
  • Preventive designs—these are work processes that make it difficult, but not impossible, to commit an error.
  • Fail-safe designs—these are work processes that reduce the consequences of an error if one is made while engaging in the task, without necessarily reducing the likelihood of making a mistake.

The organization must devise systems that enable safe performance as well as systems that sustain those safe behaviors.

Safe Work Execution Process

The safe work execution process is based on scientifically proven research. Consequence management is based on the operant condition theory resulting from B.F. Skinner's research. To effectively change the worker's behavior, the organization should devise a safe work execution (SWE) program as well as process. This entails carefully analyzing task work activities to identify risk associated with each key task function (KTF). This involves the following.

  • Design of a safe work execution program
    • Analyze typical work activities to identify key task functions.
    • Educate workers on KTFs.
    • Create an inspection form based on KTF elements.
    • Designate staff responsible for SWE inspections.
  • Perform a comprehensive project risk assessment to identify all potential risk of injury, the level of exposure of those risks, and the severity of the potential outcomes for all physical condition as well as all KTF.
    • Physical, work process, worker action, or hazards evaluation
    • Degree of exposure determination
    • Risk mitigation plan (reduce all risk to an acceptable level)
    • Inform (and train if needed) prior to work execution.
  • Manage consequences to affect worker behavior.

After having done the risk assessment and identified the safest way to do that work, the workforce must be informed of this. Any remaining residual risk must be discussed with the workforce members so that they are aware of it and know how to effectively deal with it. Also, review the KTFs to ensure everyone knows the best and safest way to perform the work. Supervision must use the KTF list to inspect the work to ensure it is being performed properly.

The safe work execution process requires that workers be given feedback on how they are doing. Anyone found performing the work in an at-risk way must be given "constructive" feedback. The intent of this feedback is to discuss the appropriate behavior and encourage workers to change their behavior to the one that is appropriate and safe. Constructive feedback is provided until the worker changes their behavior to the accepted method. Feedback can also be provided to extinguish unsafe or unacceptable behavior.

At times, safe behaviors may not be well supported in the natural work environment—either consciously or unconsciously. To encourage workers to continue utilizing the proper safe work techniques, "appreciative" or reinforcing feedback comes into play. This involves periodically recognizing workers for continuing to perform their work in the expected fashion. This feedback helps to motivate workers to continue working in the prescribed manner and so sustains the "safe" behavior over time. A way to strengthen the feedback process or increase the influence on changing or sustaining behavior is through the application of Richard Thaler's "nudge theory."

Defining Nudges

Generally speaking, a nudge is a prod or touch that may try to attract one's attention, direct one's focus, or point out something of interest or importance. The utilization of nudging is a deliberate approach to encourage suitable thinking that precedes appropriate decision-making, resulting in proper behavior. This has proven to be significantly more efficient as well as far more effective than the traditional approach of enforcing policies or procedure or the leveling of threats or punishment, to name a few. There are no negative consequences if one fails to heed a nudge; yet, conversely, it does make it easier for people to make the appropriate choice or decision.

A nudge or nudges enhance the likelihood that an individual will make a particular choice or engage in a specific activity by changing the environment so as to trigger automatic cognitive processes that favor the desired outcome. Central to nudging is the fact that people tend to think as well as make decisions instinctively rather than logically. Research has shown that humans are not totally rational beings. At times, an individual's behavior may not be aligned with their intentions. People have been known to do things that may not be in their best interest.

Nudging offers clues that enable people to improve their thinking, which enhances the implementation as well as the management of change. The nudge theory introduces a subtle means to enhance and support decision-making.

There are a number of different nudge characteristics or techniques. These include default nudges and social proof heuristics, as well as those that focus attention or increase the obvious benefit of the preferred alternative or choice.

  • Default options are those that will occur if the individual does not do anything different. Since this takes less effort, people may tend to defer to such choices.
  • Social proof heuristics refer to the likelihood of individuals to look to what others are doing as a guide to it being a safe choice on their part.
  • Things that focus attention by pointing out benefits, making selection easier or more attractive, or highlighting benefits or value tend to become more salient to the individual, thereby making it more likely that that option will be chosen.

The Nudge Theory

A more effective way to initiate change in behavior is through the application of the nudge theory. Though this theory was originally proposed in "behavioral economics," it can easily be adapted and applied much more widely for enabling and encouraging change in behavior of individuals, groups, or organizations. This is a theory that was popularized with the publication of a book in 2008. Nudge: Improving Decisions about Health, Wealth, and Happiness was written by Richard Thaler and Cass R. Sunstein. This book is based on the work done in the 1970s by the Nobel prize-winning psychologists Daniel Kahneman and Amos Tversky.

Mr. Kahneman and Mr. Tversky's work focused on judgment and decision-making. They proposed that heuristics are rooted in the idea that a variety of factors cause people to think and decide instinctively rather than logically and that this can be anticipated, specified, and predicted. Central to behavior is decision-making from the choices available at the point in time that decisions are being made. Thaler and Sunstein equate this concept to "nudges." The "nudge" process facilitates better understanding as well as management of the "heuristic" influences on human decision-making and behavior, which is central to fostering change in people.

The universal application of the nudge theory was launched by a news article in 2009 about a simple but effective solution to a chronic maintenance and hygiene problem in the men's bathrooms at Amsterdam's Schiphol Airport. They installed small fly-shaped stickers in the men's urinals so that men had something to aim at. This reduced spillage by over 80 percent. The nudge theory is a flexible change-management concept for the following.

  • Understanding how people think, make decisions, and behave
  • Enabling people to improve their thinking process and resulting decisions
  • Managing change that influences and transforms behavior
  • Identifying, altering, or removing existing counterproductive influences on people

Organizations soon found that nudges are far more effective than any signage that tries to inform people or threatens them with fines if they choose to ignore the information provided by the signs. Below is a comparative chart of traditional interventions compared to those reflecting nudge thinking.

Traditional Interventions

  • Direct, obvious
  • Rules, guidelines
  • Policing, enforcement
  • Instruction, direction
  • Imposed choices
  • Deadlines
  • Pressure
  • Tell, talk down to
  • Selective information

Nudge Interventions

  • Indirect, subtle
  • Enablement, facilitation
  • Assistance, support
  • Educate, inform
  • Freedom to choose
  • Open-ended
  • No pressure
  • Discuss, share
  • Openess, nothing withheld

The nudge theory strives to improve the understanding as well as the management of the heuristic influences on human behavior. Central to behavior is decision-making from the known choices available at that point in time. By "designing" the choices, decisions are influenced, and behavior is channeled to an appropriate level. The designing of choices must be congruent with the way people actually think, which is instinctive rather than rational. As a result, nudge theory is a dramatically different approach to managing change in people through indirect means and methods as opposed to the traditional direct approach of instruction, direction, enforcement, or punishment. Those organizations that have implemented "nudge" thinking in their operations have found that it dramatically affected thinking about and methods used for motivating and changing people's choices, decisions, or actions.

Application of Nudging

Nudging is a method of influencing people to make the appropriate choices. There are many examples of this. In marketing, the use of nudges such as "most popular" or "best-selling" product indicates that many people have determined the value or usefulness of it and may nudge another person's choice to also select that particular product. One marketer's advice to trainees: "Since 95 percent of people are imitators, and only 5 percent are initiators, people are more likely to be persuaded by the actions of other than by any proof we may provide."

A researcher placed a number (four to six) of his assistants on busy sidewalks in New York City, asking them to stare at an empty spot in the sky or a tall building, while a third person observed the behavior of the people walking by. The average number of people pausing to look up was anywhere from 80 percent to 90 percent. The action of the researchers nudged the curiosity of the people to stop and find out what was causing them to stare up.

Exposure and Work Practices

Injuries from construction accidents are costly in terms of human suffering and operational losses. There are fallacies at play in the management of safety in construction. One of these is the belief that the utilization of OSHA standards in training workers will result in fewer accidents. Underlying this is the belief that rational people do not want to get hurt and that providing them with the knowledge of how to avoid getting hurt will change their at-risk behavior.

But, it is a proven fact that humans may perceive risk in a skewed sense. This understanding of risk is reinforced daily in the work activity of people by small and regular rewards. People performing their daily tasks usually find ways to make it easier or take less time or effort, which may involve taking some risk with no adverse effect. Over time, these benefits diminish the treatment of the risks and eventually normalize at-risk behavior.

This understanding highlights the reason why workers underestimate risks associated with the work, their exposure to hazards, or how their at-risk behavior is incentivized by the lack of adverse outcomes. Generally, this action increases productivity, which is recognized by the supervisor, thereby reinforcing the risk-taking until an accident occurs. This then draws attention to the areas where faulty risk perception had led to negative outcomes. These low-frequency/high-consequence events start the reactive process of informing all the workers on how to avoid such accidents in the future by way of writing procedures, putting up signage, or providing training materials.

A significant example of this involves the use of seatbelts in automobiles. When wearing seatbelts was optional, a survey found that less than 20 percent of drivers were using them. Drivers engaged in this behavior in spite of the fact that they were aware of the serious number of injuries and fatalities that resulted from traffic accidents. This highlighted the perceived expected daily benefit (save time, less discomfort, less wrinkled clothing, etc.) outweighing the rare negative consequence of an accident, injury, etc. See "Normalization of Performance Deviations" (August 2014). To ensure that drivers engaged in the appropriate behavior, the wearing of seatbelts had to be made mandatory.

Nudges are utilized by many astute organizations. Some nudges are obvious, while others are subtle. In hospitals or clinics, colored lines on the floor guide patients to the "right" departments. This is an example of a subtle nudge. In supermarkets, certain items are placed in front of the entrance, at the end of aisles, or on eye-level shelves to enhance their purchase. In movie theaters during the previews, multiple clips of soda and popcorn are shown to (nudge) encourage people to buy some. Organizations have found that placing refuse containers in prominent locations and in sufficient numbers reduces littering more effectively than signs threatening fines. Nudges are also common in advertising and marketing.

The nudge theory is mainly concerned with the design of choices, which influences the decisions people make. In this respect, nudge theory is a different and more sophisticated approach to enabling people to change than traditional methods of training, instruction, enforcement, rewards, and/or punishment. The use of nudge theory is based on indirect encouragement and enablement. Nudging avoids direct instruction or enforcement. Central to the nudge concept is that people can be guided to think appropriately to make better decisions by being offered choices that have been designed to enable "better" outcomes.

Application of Nudging in Safety Management

Application of behavioral theory to safety has been around for over 40 years. Many organizations have implemented some form of it, with varying degrees of success. The underlying theory of this process is operant conditioning. A practical means of accomplishing this is by using the SWE process discussed in the October 2018 article. To make this process more effective, organizations must add the nudging theory to their safety management program as well as process.

Nudging increases the effectiveness of positive reinforcement (consequence management) of behavior by hinting and/or offering suggestions, which influence motivation in the decision-making process of individuals. Research has shown that nudging is often more effective than the traditional means for garnering safe behavior through training, inspections, incentives, or punishment. Nudging is especially successful in fostering safe behavior if the individual is unaware that their thought process, decisions, and behavior are being influenced by external forces.


Nudging has the potential to more effectively change behavior and improve safety results where regulation and enforcement have often failed, and behavior-based safety has had less than universal stellar results. The application of nudging in the management of safety by way of changing worker behavior has had some consequential success in the United Kingdom, Canada, and Australia. Nudging, the structuring of choice and influencing decision-making, is an additional tool for safety managers to use to change worker behavior. The real success of nudging will materialize when the nudge is indirect or becomes second nature.

Some innovative organizations have successfully applied nudging. But, for the construction industry to utilize it universally, some research will have to be conducted to highlight its successes.

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